Clearly that last comment was considerate. Lord knows we should all answer to people who
know people who can draw.
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Here, I drew this up to help you. I did it pretty quickly, but yeah, anyways.
You can see how the human body is built up of different shapes. The spine is outlined in red, and the weight is shown in red arrows. The direction of the weight will determine how the body reacts to the pose and how the clothes will. The purple lines show the tilt of the shoulder and hips.
You might notice the legs look funny. This is because of the weight distribution. By looking at the direcional arrows, you can see that even with the fence there, she would fall over. It's a very unnatural pose. Try doing it yourself. The solution to this would be that instead of bending her left leg at the knee, to have it move in the right direction from the hip. The foot also wouldn't go out so far.
It's a good idea to take poses from reference pictures, or to stand in front of a mirror and do it yourself when you're first starting a drawing. I do this with everything. The good thing about doing it yourself is that you have more freedom. The bad thing is that you have to draw while keeping the pose, and also you can't get interesting angles. Using reference pictures is great for more complex poses.
Keep in mind these are manga proportions so if you want it to look more realistic, use a more egg-shaped torso and shorter legs.
I'm not saying everybody does, but a lot of people start their drawings this way. It helps you to spot any problems from the beginning, and also keep your figure constant. Besides, it's easier to draw a model and put clothes on them, than to draw clothes and put a model in it.
Stepping away from body proportion for a second, I'm going to mention a flaw in the face. The nose goes much too high. If you notice, your nose comes to an end where your eye is.
http://www.michelejaco.com/Michele Jaco Headshot.JPG
Keeping this in mind, try re-drawing the picture. You'll find that when you start breaking your drawings down this way it'll be a lot easier.
Hope that helped!